The present invention relates to a heart rate monitor, and more particularly, to a heart rate monitor which can be incorporated into wrist watches, belt-clip devices and the like for allowing the user to obtain solely by inputting age data and/or to reset default high and low range settings for maintaining heart rate level, measured in beats per minute (bpm), during, for example, aerobic conditioning.
Current practices and thinking involving effective aerobic conditioning hold that the appropriate heart rate level must be maintained for at least twenty minutes each workout in order to benefit the exerciser. This level or heart rate range is also referred to as the "target zone", a range of values measured in terms of bpm. One generally accepted approach for determining a person's target zone is to use the formula EQU MAX HEART RATE=220-AGE
and then using between 50% to 90% of the maximum heart rates. Of course, this will also depend somewhat on a person's general conditioning. For example, the American Heart Association recommends that an inactive person exercise in ten to fifteen minute sessions with a lower target zone of 50% and an active person in at least thirty minute sessions with an upper target zone of 85%.
Those involved in aerobic conditioning will also be aware of alternative conventional ways for determining a target zone. Their methods include using different percentages, and adding or subtracting numbers from the maximum heart rate depending upon physical condition or other relevant criteria. Alternatively, or in addition, heart rate levels can be measured and tracked during the exercise or conditioning periods using wireless monitors.
As is also well known, such monitors measure the actual electrical ECG signals from the person's chest skin via a chest belt transmitter which transmits, for example, a signal to a wrist display via a high frequency field. The wrist display electronics receive the signals, interpret them and display the actual current bpm. Commercially available wristwatch-style heart monitors include the "Heartsafe-T" and the "2000" offered by Cardiosport USA Ltd. of Overland Park, Kans., the "Accurex", "Edge", "Pacer", "Favor", "Vantage XL" and "Cyclovantage" offered by Polar Electro Inc. of Port Washington, N.Y., and the "CARDIOCHAMP" offered by Systems Dynamics. Typically, such devices will display time-of-day, elapsed time, heart rate recording and target zone, average heart rate and so on.
Conventional wireless heart rate monitors typically require, however, that the user manually program his or her specific high and low range settings. In order to do this properly, the user must know one of the several target-zone formulas and how to calculate individual ranges or to have a chart available for obtaining the range. In either case, the range values must be then manually input.
It is an object of the present invention to provide a greatly simplified wireless heart rate setting and monitoring method and device which allows the user to obtain the appropriate target zone automatically merely by entering his or her age. The target zone, e.g. 65% to 85% of maximum heart rate, will then be calculated according to any one of a number of algorithms which can be pre-programmed and/or later programmed in the application software of a microprocessor within a device worn by the person.
An advantage of the present invention is that a target zone can be instantly calculated using a variety of formulas which can also take account of physical condition, gender, etc., but which is primarily based and completely set by the user merely by inputting his or her age.
This object and advantage has been achieved by providing a wireless heart rate monitor in the form of a display device, i.e. a display worn on the exerciser's wrist or a belt-clip device, and a wireless transmitter belt worn on the chest in proximity to the heart for transmitting electrical signals representative of heart rate to the wrist or belt display device.